Pompe hydraulique HPV118HW 9262321 9262324 pour excavateur Hitachi ZX225US-3 ZX225USR-3

1. Product Identification & Compatibility
This pump assembly is the official replacement for the following Hitachi factory part numbers:

Model Number: HPV118HW

Hitachi OEM Part Numbers: 9262321, 9262324

Machine Fitment:

Hitachi ZX225US-3 (Ultra Short)

Hitachi ZX225USR-3 (Ultra Short Radius)

2. Technical Specifications
Type: Tandem Variable Displacement Axial Piston Pump.

Pressure Rating: Capable of sustained high-pressure output at 34.3 MPa (343 bar).

Flow Sharing: Integrated with regulators designed for flow-sharing efficiency, allowing for seamless simultaneous operations (e.g., booming up while swinging).

Design: Compact tandem configuration allows the pump to fit within the restricted engine compartment dimensions of the US-3 chassis.

3. Why Choose the Original Brand?
For the ZX225-3 series, the difference between an Original Brand pump and an aftermarket clone is significant:

Regulator Precision: The HW series regulators are factory-calibrated to the torque curve of the Isuzu engine. Aftermarket pumps often cause "hunting" (engine RPM instability) or stalling during heavy lifts.

Metallurgical Strength: Original cylinder blocks and valve plates utilize high-grade hardened alloys. This is vital for resisting cavitation, which is the leading cause of internal pump erosion in high-cycle excavation.

Seal Integrity: Genuine units come equipped with high-temperature Viton or specialized polymer seals that prevent case pressure leaks, ensuring the pump stays dry and efficient for its full service life.

4. Expert Installation Protocol
To ensure the longevity of your new 9262321 / 9262324 pump, these steps are mandatory:

Case Priming: CRITICAL. You must manually fill the pump housing with clean hydraulic oil through the highest case drain port before starting the engine. Starting a pump "dry" will destroy the internal bronze slippers and swash plate in seconds.

Oil Quality: Use only high-quality ISO VG46 anti-wear hydraulic oil.

Filter Change: Always replace the suction strainer and the return filter. If the previous pump failed mechanically, you must flush the oil cooler and lines to remove metal debris.

Air Purging: After startup, run the engine at low idle for 10 minutes. Gently cycle all cylinders to their stroke ends to purge air from the system.

5. Frequently Asked Questions (FAQ)
Is the HPV118HW interchangeable with the HPV118JX found in the Dash-5 series?
No. While they share the same displacement (118cc), the mounting pilots, input shafts, and regulator control logic are different. You must use the "HW" variant specifically for the Dash-3 machines.

How do I know if my pump needs replacing or just a regulator adjustment?
If your machine is slow in all functions or stalls the engine, it is likely the pump or regulator. However, if only one function (like bucket curl) is weak, the issue may be in the main control valve or the cylinder. We recommend a flow and pressure test before replacement.

What is the expected lead time?
We typically stock these units for immediate dispatch. Global express shipping via DHL, FedEx, or UPS usually arrives in 3 to 7 business days.

Does the pump come with a warranty?
Yes, our Original Brand New pumps come with a standard factory warranty, provided the installation protocols (including case priming and filter changes) are documented.